UL 462:2010 pdf download.Heat Reclaimers for Gas-,Oil-, or Solid Fuel-Fired Appliances.
9.2.7 Hinged covers,where required，shall not depend solely upon screws or other similar meansrequiring the use of tools to hold them closed, but shall be provided with a catch or spring latch.
9.2.8 A spring latch, a magnetic latch, a dimple, or any other mechanical arrangement that will hold thedoor in place and would require some effort on the user's part to open it is considered to be a means forholding the door in place as required in 9.2.7.
9.2.9 A door or cover giving direct access to fuses in other than low-voltage circuits shall shut closelyagainst a 1/4-inch (6.4-mm) rabbet or the equivalent, or shall have either turned flanges for the full lengthof four edges or angle strips fastened to it. Flanges or angle strips shall fit closely with the outside of thewall of the box proper and shall overlap the edges of the box not less than 1/2 inch(12.7 mm).Aconstruction which provides equivalent protection, such as a fuse enclosure within an outer enclosure ora combination of flange and rabbet may be used.
9.2.10 Strips used to provide rabbets, or angle strips fastened to the edges of a door,shall be securedat not less than two points，not more than 1-1/2 inches (38.1 mm) fromi each end of each strip and atpoints between these end fastenings not more than 6 inches (152 mm) apart.
9.3 Openings
9.3.1During the examination for conformance with the requirements of 9.3.3,9.3.4,and 9.3.5, a part ofthe enclosure, including air filiters, which may be removed without the use of tools, is to be removed.9.3.2 The acceptability of openings in an enclosure shall be determined on the basis of possible emissionof flame,burning particles and molten metal and accessibility of bare live parts and fim-coated wire inaccordance with 9.3.4 -9.3.13.
9.3.3 An opening in an enclosure to provide clearance around a dial, knob, lever, or handle shall not allowthe entrance of a rod having a diameter of 9/64 inch (3.6 mm) at any setting or position of the dial, knob,or the like. The probe illustrated by Figure 9.1 shall not contact uninsulated live part or film-coated wirethrough such opening.
